Ultrasound biomicroscopy in the diagnosis and management of intraocular gnathostomiasis

Case Report: Ocular Manifestations and Treatments of Ciliary Body Involvement by Lymphoma

Purpose

To describe the ocular clinical features, histopathological findings, and treatment outcomes of lymphomas involving the ciliary body.

Methods

We demonstrate three cases of ciliary body involvement by lymphoma from 2013 to 2019 in Peking Union Medical College Hospital (PUMCH). All patients underwent examinations including best corrected visual acuity (BCVA), slit-lamp microscopy, indirect ophthalmoscope, ultrasound biomicroscopy (UBM), and diagnostic vitrectomy. In addition, cytopathology, immunohistochemistry, gene rearrangement, cytometric immunophenotypic, or in-situ hybridization were used for determining the pathological type of lymphoma.

Results

The patients were a 25-year-old man, a 52-year-old woman, and a 54-year-old man. Two patients had unilateral involvement, and one patient had bilateral involvement. All patients presented with anterior uveitis and elevated intraocular pressure. Ciliary body masses or infiltration were found in 3 patients. Two patients had diffuse large B-cell lymphoma and one patient had natural killer/T-cell lymphoma. All patients received 0.4 mg methotrexate intravitreal injections, and the ciliary body lesions regressed completely.

Conclusion

Lymphomatous involvement of the ciliary body usually presents as an atypical anterior chamber reaction. Vitreous biopsy should be considered in these patients for diagnosis. Methotrexate intravitreal injection combine with chemotherapy or radiotherapy, might extend the survival time and preserve visual acuity for patients with ciliary body involvement by lymphoma.

Human gnathostomiasis: a neglected food-borne zoonosis

BACKGROUND

Human gnathostomiasis is a food-borne zoonosis. Its etiological agents are the third-stage larvae of Gnathostoma spp. Human gnathostomiasis is often reported in developing countries, but it is also an emerging disease in developed countries in non-endemic areas. The recent surge in cases of human gnathostomiasis is mainly due to the increasing consumption of raw freshwater fish, amphibians, and reptiles.

METHODS

This article reviews the literature on Gnathostoma spp. and the disease that these parasites cause in humans. We review the literature on the life cycle and pathogenesis of these parasites, the clinical features, epidemiology, diagnosis, treatment, control, and new molecular findings on human gnathostomiasis, and social-ecological factors related to the transmission of this disease.

CONCLUSIONS

The information presented provides an impetus for studying the parasite biology and host immunity. It is urgently needed to develop a quick and sensitive diagnosis and to develop an effective regimen for the management and control of human gnathostomiasis.

Ocular Gnathostomiasis Presenting as Branch Retinal Artery Occlusion

PURPOSE

To report a case of ocular Gnathostomiasis presenting as branch retinal artery occlusion.

METHOD

Observational case report.

RESULT

A 22-year-old Asian woman presented to her ophthalmologist with redness, tearing, and decreased vision in her left eye. Examination revealed anterior uveitis and branch retinal artery occlusion associated with both intra-retinal and vitreous hemorrhage. The patient was treated with topical corticosteroids and cycloplegics. After 3 weeks, she presented in our emergency, with further decrease in vision and worsening pain in the left eye. Slit lamp examination revealed a brown colored live worm on the posterior corneal surface, anterior uveitis, multiple iris holes, and vitreous cells. Indirect ophthalmoscopy showed focal retinal hemorrhages, subretinal tracts, and vitreous hemorrhage. Surgical removal of the worm from anterior chamber was done immediately.

CONCLUSION

Branched retinal artery occlusion with intraretinal and vitreous hemorrhage, panuveitis, and multiple iris holes may suggest the presence of an intraocular parasite.

Three-dimensional spectral domain optical coherence tomography and light microscopy of an intravitreal parasite

BACKGROUND

Various imaging modalities play a role in diagnosing parasitic infections of the eye. We describe the spectral domain optical coherence tomography (SD-OCT) findings of an intravitreal parasite with subsequent evaluation by light microscopy.

FINDINGS

This is a case report of a 37-year-old Ecuadorian man who presented with uveitic glaucoma and a new floater in his left eye for 1 week's duration. Full ophthalmic examination revealed an intravitreal parasite. Color fundus photography, fluorescein angiography (FA), ocular ultrasonography (US), and SD-OCT were performed. The parasite was removed via 23-gauge pars plana vitrectomy and sent to pathology for evaluation. Color fundus photography and ocular ultrasonography demonstrated an elongated foreign body within the vitreous above the retina. FA demonstrated minimal vascular changes in the vicinity of the parasite. SD-OCT was utilized to visualize the parasite and to create a three-dimensional (3D) image. The parasite was determined to be most consistent with Gnathostoma spp. by morphologic analysis.

CONCLUSIONS

This is the first reported case of SD-OCT of an intravitreal parasite with corresponding evaluation by pathology. SD-OCT allows non-invasive, high-resolution visualization and 3D reconstruction of parasitic anatomy which may help establish tomographic criteria for species identification.

A rare case of cutaneous larva migrans due to Gnathostoma sp

A 28-year-old lady presented with recurrent erythematous skin lesions in different parts of the body for 3 months. There were several episodes of worm coming out of the lesions. Examination of the worms in the parasitology laboratory revealed it to be a larva of Gnathostoma sp. She was advised treatment with Albendazole for 21 days, and there was no recurrence of lesions.

Intraocular gnathostomiasis: report of a case and review of literature

Intraocular gnathostomiasis is a rare parasitic infection caused by the third-stage larvae of spiruroid nematode Gnanthostoma spp. seen mostly in tropical and subtropical regions. It is a food-borne zoonosis caused by ingestion of raw or undercooked freshwater fish, amphibians, reptiles, birds, and mammals, all of which are known to harbor advanced third-stage larvae of Gnanthostoma spp. To date, 74 cases of intraocular gnathostomiasis have been reported from 12 different countries. Only four countries have reported more than 10 cases each, and India shares the rare distinction of being one of them, with 14 cases. Surprisingly, not a single case of cutaneous gnanthostomiasis has ever been reported from India. We present one such case of intraocular gnathostomiasis in a 41-year-old male who presented with an actively motile worm attached to the iris, and we review the pertinent literature of all such cases reported from India.

Zoonotic helminths affecting the human eye

Nowaday, zoonoses are an important cause of human parasitic diseases worldwide and a major threat to the socio-economic development, mainly in developing countries. Importantly, zoonotic helminths that affect human eyes (HIE) may cause blindness with severe socio-economic consequences to human communities. These infections include nematodes, cestodes and trematodes, which may be transmitted by vectors (dirofilariasis, onchocerciasis, thelaziasis), food consumption (sparganosis, trichinellosis) and those acquired indirectly from the environment (ascariasis, echinococcosis, fascioliasis). Adult and/or larval stages of HIE may localize into human ocular tissues externally (i.e., lachrymal glands, eyelids, conjunctival sacs) or into the ocular globe (i.e., intravitreous retina, anterior and or posterior chamber) causing symptoms due to the parasitic localization in the eyes or to the immune reaction they elicit in the host. Unfortunately, data on HIE are scant and mostly limited to case reports from different countries. The biology and epidemiology of the most frequently reported HIE are discussed as well as clinical description of the diseases, diagnostic considerations and video clips on their presentation and surgical treatment.